Semiconductor device and method of producing the same

ABSTRACT

A semiconductor device and a method of producing the same are provided. The semiconductor device includes: a semiconductor chip; a resin package which seals the semiconductor chip; signal passages which guide the signal terminals of the semiconductor chip outward from the resin package; a grounding metal film in contact with the bottom surface of the semiconductor chip; and a grounding passage which is connected to the grounding metal film and guided outward from the resin package.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a semiconductor device and a method ofproducing the same.

2. Description of the Related Art

In recent years, semiconductor devices have been becoming smaller andmore highly integrated. Along with this trend, more and more wrongoperations and unstable characteristics are seen in a semiconductordevice due to interference between regions having different functions.

In view of this, there has been an increasing demand for semiconductorsin which no interference is caused between regions having differentfunctions.

FIGS. 11A and 11B are a sectional view and a perspective view of aconventional semiconductor device. A CSP (Chip Size Package)semiconductor device is shown in the figures.

In a conventional semiconductor device 81 shown in FIG. 11A, asemiconductor chip 82 is sealed in a resin package 83. Signal terminalson the surface of the semiconductor chip 82 are electrically connectedto mounting protrusions 85 protruding from the bottom surface of theresin package 83 by wires 84.

The surfaces of the mounting protrusions are covered with metal films86, and the bottom surface of the semiconductor chip 82 is coated withan insulating adhesive 89.

As shown in FIG. 11B, the semiconductor chip 82 is situated in thecenter of the semiconductor device 81, and the metal films 86 (or themounting protrusions 85) are situated in the surrounding area of thesemiconductor chip 82. The metal films 86 are connected to the signalterminals of the semiconductor chip 82 by the wires 84.

The signal terminals of the semiconductor chip 82 include terminalswhich input and output various signals, and a grounding terminal whichserves as a reference potential.

Since semiconductor devices have been becoming smaller and more highlyintegrated, regions having various functions exist in a small area. FIG.12 is an enlarged sectional view of a part of the conventionalsemiconductor device, illustrating the problems in the prior art.

The semiconductor device 81 shown in FIG. 12 has a PLL (Phase LockedLoop) circuit, for instance. The semiconductor chip 82 contains aplurality of functional regions including a first functional region 90and a second functional region 91. The functional regions are formedwith a semiconductor substrate 87 as a base, and are divided byisolators 92.

A wiring pattern 93 is formed on the surfaces of the first functionalregion 90 and the second functional region 91, and a part of the wiringpattern 93 is connected to a grounding terminal 94 which is a referencepotential. The grounding terminal 94 also serves to release small noiseexisting inside the semiconductor substrate 87, and is formed on one ofthe isolators 92.

The bottom surface of the semiconductor chip 82, i.e., the bottomsurface of the semiconductor substrate 87, is coated with the insulatingadhesive 89.

Since the semiconductor device 81 is extremely small and highlyintegrated, the first functional region 90 and the second functionalregion 91 are disposed in an extremely small area, though they havedifferent functions.

In the PLL circuit, frequency conversion is performed by a divider togenerate a plurality of frequencies. For instance, the first functionalregion 90 operates on a frequency f1, while the second functional region91 operates on a different frequency f2.

With such a structure, the frequency leaking from each region turns intonoise that enters the neighboring functional region, as indicated byarrows in FIG. 12. The noise often results in unstable characteristicsor wrong operations.

The grounding terminal 94 disposed on the isolator 92 cannot releaseenough noise, because the first functional region 90 and the secondfunctional region 91 are too close to each other. It is possible torelease all noise by forming a plurality of grounding terminals at shortintervals, but such a measure is not suitable for the highly-integratedsmall-size semiconductor device.

SUMMARY OF THE INVENTION

A general object of the present invention is to provide a semiconductordevice and a method of producing the same in which the abovedisadvantages can be eliminated.

A more specific object of the present invention is to provide a highlyintegrated small semiconductor device in which adverse influence due tointerference between different functional regions are prevented toachieve stable operations.

The above objects of the present invention are achieved by asemiconductor device which includes: a semiconductor chip: a resinpackage which seals the semiconductor chip; signal passages which guidesignal terminals of the semiconductor chip outward from the resinpackage; a grounding metal film in contact with a bottom surface of thesemiconductor chip; and a grounding passage which is connected to thegrounding metal film and is guided outward from the resin package.

In this structure, the grounding metal film is in contact with thebottom surface of the semiconductor chip, so that unnecessary electricsignals in the semiconductor chip are absorbed by the metal film andreleased outward. Thus, wrong operations due to interference betweenregions having different functions can be prevented.

The resin package of the semiconductor device has a plurality ofmounting protrusions covered with metal films. The metal films on themounting protrusions and the signal terminal of the semiconductor chipare connected by conductive wires to form the signal passages.

In this structure, there is no need to employ lead terminals extendingoutward from the semiconductor chip, and the mounting protrusionscovered with the metal films serve as outer terminals immediately belowthe semiconductor chip. Thus, the semiconductor device can remain smallin size, and unnecessary noise in the semiconductor chip can be releasedto the outside.

The above objects of the present invention are also achieved by a methodof producing a semiconductor device in which a semiconductor chip issealed in a resin package having a plurality of mounting protrusions sothat signal terminals of the semiconductor chip are guided outward fromthe mounting protrusions. This method includes the steps of: attachingmetal films onto the inner surfaces of concavities corresponding to themounting protrusions, and to a semiconductor chip mounting surfacesurrounded by the concavities formed in a base; mounting thesemiconductor chip onto the metal film surrounded by the concavities viaa conductive adhesive; electrically connecting the signal terminals ofthe semiconductor chip to the metal films on the inner surfaces of theconcavities by conductive wires; sealing the semiconductor chip and theconductive wires with resin; and detaching the base from the metal filmson the inner surfaces of the concavities and the semiconductor chipmounting surface.

By this method, the grounding metal film can be formed at the time ofthe formation of the metal films on the mounting protrusions as theouter signal terminals. Thus, unnecessary noise in the semiconductorchip can be removed without complicating the production procedures.

The above and other objects and features of the present invention willbecome more apparent from the following description taken in conjunctionwith the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B are a sectional view and a bottom view of asemiconductor device of a first embodiment of the present invention;

FIGS. 2A to 2H are sectional views illustrating the productionprocedures of the first embodiment of the present invention;

FIG. 3 is a sectional view of mounted semiconductor devices of the firstembodiment of the present invention;

FIGS. 4A and 4B are a sectional view and a perspective view of asemiconductor device of a second embodiment of the present invention;

FIGS. 5A to 5H are sectional views illustrating the productionprocedures of the second embodiment of the present invention;

FIG. 6 is a partially enlarged view of the semiconductor device of thesecond embodiment of the present invention;

FIGS. 7A and 7B are a sectional view and a perspective view of asemiconductor device of a third embodiment of the present invention;

FIGS. 8A and 8B are a sectional view and a perspective view of asemiconductor device of a fourth embodiment of the present invention;

FIGS. 9A and 9B are a sectional view and a perspective view of asemiconductor device of a fifth embodiment of the present invention;

FIGS. 10A and 10B are a sectional view and a perspective view of asemiconductor device of a sixth embodiment of the present invention;

FIGS. 11A and 11B are a sectional view and a perspective view of asemiconductor device of the prior art; and

FIG. 12 is a schematic sectional view showing problems in the prior art.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following is a description of embodiments of the present invention,with reference to the accompanying drawings.

A semiconductor device 1 of this embodiment is a CSP (Chip Size Package)having no lead terminals. As shown in FIG. 1A, a resin package 3 isprovided with mounting protrusions 5 and a grounding protrusion 7, and asemiconductor chip 2 is disposed inside the grounding protrusion 7. Themounting protrusions 5 and the grounding protrusion 7 are covered withmetal films 6 and a metal film 8, respectively.

Signal terminals formed on the surface of the semiconductor chip 2 areelectrically connected to the metal films 6 on the surfaces of themounting protrusions 5 of the resin package 3 by wires 4.

The bottom surface of the semiconductor chip 2 sealed in the groundingprotrusion 7 of the resin package 3 is electrically in contact with themetal film 8 by a conductive adhesive 9.

As shown in the bottom view in FIG. 1B, the metal film 8 correspondingto the grounding protrusion 7 is formed in the center of thesemiconductor device 1. The metal films 6 corresponding to the mountingprotrusions 5 are formed around the metal film 8. The semiconductor chip2 is sealed in the resin package 3 as indicated by a dot-and-dash linein the metal film 8.

In this embodiment, the semiconductor chip 2 has a semiconductorsubstrate made of silicon, for instance, as a base. The conductiveadhesive 9 on the bottom surface of the semiconductor chip 2 is silverpaste. With this structure, a grounding passage from the semiconductorsubstrate is formed via the silver paste.

Referring now to FIGS. 2A to 2H, a method of producing the abovesemiconductor device will be described below.

As shown in FIG. 2A, a resist 12 having a predetermined pattern isattached to the upper surface of a metal plate made of copper, forinstance. A resist covers the entire lower surface of the metal plate11.

The exposed portions of the metal 11 are etched, with the resist 12serving as a mask, so that concavities 13 a and 13 b are formed as shownin FIG. 2B. Here, a cover pattern may be formed on the resist 12depending on the adjustment of the speed of the etching, i.e., the areain which the etching is performed to form concavities having the samedepth.

The concavities 13 a and 13 b formed by the etching are then plated, sothat the metal films 6 and 8 shown in FIG. 2C are formed. The metalfilms 6 and 8 have a multi-layered structure to obtain adhesion andstrength with a conductive material (soldering) used at the time ofmounting.

The resist 12 is then removed so that a lead frame shown in FIG. 2D iscompleted.

As shown in FIG. 2E, The semiconductor chip 2 is mounted on the metalfilm 8 in a position corresponding to the concavity 13 b of the leadframe 14. Here, the conductive adhesive 9 made of silver paste isinterposed between the metal film 8 and the semiconductor chip 2. Thesilver paste includes a dilution of epoxy or the like, which might causea blur. This can be prevented by forming non-plated portions on themetal film pattern. By doing so, the resin of the resin package isbrought into contact with the non-plated portions to prevent a blur.

After the semiconductor chip 2 is mounted, the signal terminals on thesurface of the semiconductor chip 2 and the metal films 6 correspondingto the concavities 13 a are electrically connected by bonding the wires4, as shown in FIG. 2F.

The resin package 3 is then formed, as shown in FIG. 2G, by a sealingtechnique using a conventional metal mold.

Finally, the metal plate 11 is removed by etching, and the semiconductordevice 1 is completed as shown in FIG. 2H.

In the production method of this embodiment, individual semiconductordevices can be formed separately from each other, but it is moreefficient to simultaneously produce a plurality of semiconductor devicesconnected to each other. The lead frame 14 shown in FIG. 2D is amatrix-type lead frame, and a plurality of semiconductor chips 2 aremounted on the lead frame 14. After the resin sealing and the metalplate removal are carried out, the lead frame 14 is diced tosimultaneously produce the individual semiconductor devices 1.

FIG. 3 illustrates mounted semiconductor devices 1 produced by the aboveproduction method.

The metal films 6 and 8 corresponding to the mounting protrusions 5 andthe grounding protrusion 7 of each of the semiconductor devices 1 arebrought into contact with mounting regions 17 of a printed circuit board15 via a conductive material. Thus, each semiconductor device 1 ismounted onto the printed circuit board 15.

The mounting region 17, with which the metal film 8 on the groundingprotrusion 7 is in contact, is grounded. Although the grounding is onlyschematically shown in FIG. 3, the metal film 8 is actually grounded toa grounding portion via a wiring pattern formed on the surface of theprinted circuit board 15.

Each of the semiconductor chips 2 has various functional regions, andnoise from each of the functional regions leaks to the semiconductorsubstrate. In the semiconductor device 1 of this embodiment, however,the noise leaking from the semiconductor chip 2 to the semiconductorsubstrate is transferred to the metal film 8 of the grounding protrusion7 via the conductive adhesive 9. Thus, adverse influence between thefunctional regions can be prevented.

A grounding region having a large area is formed near the noisegenerating portion in the semiconductor substrate. With this groundingregion, the noise leaked from the various functional regions to thesemiconductor substrate can be discharged prior to reaching the adjacentfunctional regions. Thus, wrong operations due to interference in thesemiconductor device can be avoided to obtain stable characteristics.

Referring now to FIGS. 4A to 6, a second embodiment of the presentinvention will be described below.

This embodiment is basically the same as the first embodiment, exceptthat flat regions are formed for wire bonding of the terminals.

As shown in FIG. 4A, a semiconductor chip 22 is disposed inside agrounding protrusion 27 of a resin package 23 having mountingprotrusions 25 and the grounding protrusion 27. Metal films 26 and 28cover the surfaces and the neighborhood areas of the mountingprotrusions 25 and the grounding protrusion 27, respectively. Theneighborhood areas of the metal films 26 and 28 are flat regions 26′ and28′.

Signal terminals on the surface of the semiconductor chip 22 and theflat regions 26′ of the metal films 26 are electrically connected bywires 24. The bottom surface of the semiconductor chip 22 sealed in thegrounding protrusion 27 of the resin package 23 is electrically broughtinto contact with the metal film 28 via a conductive adhesive 29.

As shown in FIG. 4B, the metal film 28 corresponding to the groundingprotrusion 27 is formed in the center of a semiconductor device 21, andthe metal films 26 corresponding to the mounting protrusions 25 areformed in the surrounding area of the metal film 28.

The flat regions 26′ and 28′ are formed in the neighborhood areas of themetal films 26 and 28, respectively. The flat regions 26′ and 28′ areused for wire bonding, and the functions of them will be describedlater.

As in the first embodiment, the semiconductor chip 22 of this embodimenthas a semiconductor substrate made of silicon or the like as a base. Theconductive adhesive 22 on the bottom surface of the semiconductor chip22 is silver paste. With this structure, a grounding passage from thesemiconductor substrate is formed via the silver paste.

Referring now to FIGS. 5A to 5H, a production method of this embodimentwill be described below.

As shown in FIG. 5A, a first resist 32 having a predetermined pattern isattached onto the surface of a metal plate 31 made of copper or thelike. The entire bottom surface of the metal plate 31 is covered with aresist.

With the first resist 32 serving as a mask, the exposed portions of themetal plate 31 are etched to form concavities 33 a and 33 b as shown inFIG. 5B.

The inner surfaces of the concavities 33 a and 33 b are then plated toform first metal films 26 a and 28 a as shown in FIG. 5C.

The first resist 32 is then partially removed, or the first resist 32 isreplaced with a resist having a different pattern, thereby forming asecond resist 34 as shown in FIG. 5D.

With the second resist 34 serving as a mask, the exposed portions areagain plated to form second metal films 26 b and 28 b as shown in FIG.5E. The neighborhood areas of the second films 26 b and 28 b are theflat regions described above with reference to FIGS. 4A and 4B.

As shown in FIG. 5F, the resist on the bottom surface and the secondresist 34 are removed, thereby completing a lead frame 35. Thesemiconductor chip 22 is then mounted on the metal film 28 correspondingto the concavity 33 b of the lead frame 35 via the conductive adhesive29 made of silver paste. The signal terminals on the surface of thesemiconductor chip 22 and the flat regions of the second metal films 26b corresponding to the concavities 13 a are electrically connected bythe wires 24.

The resin package 23 is then formed by a conventional sealing techniqueusing a metal mold, as shown in FIG. 5G.

Finally, the metal plate 31 is removed by etching, thereby completingthe semiconductor device 21, as shown in FIG. 5H.

In the production method of this embodiment, a plurality ofsemiconductor devices 21 are simultaneously produced and then diced.

As described above, the first metal films 26 a and 28 a, and the secondmetal films 26 b and 28 b, are formed with the first resist 32 and thesecond resist 34 serving as the masks in this embodiment. The secondmetal films 26 b and 28 b are provided with the respective flat regions,and the wires 24 are connected to the flat regions.

With this structure, wire bonding can be easily carried out, because itis easier to connect the wires to the flat regions outside theconcavities 33 a than to the metal films on the inner surfaces of theconcavities 33 a.

More specifically, since each of the concavities 33 a is formed byetching a small portion of the metal plate 31, it has a hemisphericalshape without a flat surface. It is difficult to secure a wire to such ahemispherical surface, and therefore, it is necessary to form aconductive ball for connecting a wire in each of the concavities 33 a inadvance.

In this embodiment, on the other hand, the wires 24 are connected to theflat regions of the second metal films 26 b electrically connected tothe first metal films 26 a on the inner surfaces of the concavities 33a. Thus, the wire bonding can be simpler and more accurate.

The concavity 33 b for mounting the semiconductor chip 22 is alsoprovided with the second metal film 28 b having a flat region. Thesecond metal films 26 b are wire-bonded to the second metal film 28 b,so that even when the first metal film 28 a in the concavity 33 b is notin electrical contact with the printed circuit board, grounding can becarried out via the first metal films 26 a in the concavities 33 a.

As shown in FIG. 4B, a wire 24 a connects one of the flat regions 26′ tothe flat region 28′. Here, the metal film 26 connected to the wire 24 ais originally formed as a grounding terminal.

FIG. 6 is a partially enlarged view illustrating the structure of themetal films of the semiconductor device of the second embodiment.

As shown in FIG. 6, each of the first metal films 26 a corresponding tothe mounting protrusions 25 (shown in FIG. 4A) consists of a Au film 26a-1 and a Pd film 26 a-2, and each of the second metal films 26 b ismade of a Ni film 26 b-1 and a Pd film 26 b-2. The first metal films 28a and the second metal film 28 b corresponding to the groundingprotrusion 27 have the same multi-layered structure as the first metalfilms 26 a and the second metal films 28 a, respectively.

The multi-layered structure is employed in this embodiment for itsconductivity, film strength, and bonding ability. The Au films 26 a-1and 28 a-1 of the first metal layers 26 a and 28 a have excellentbonding ability with a conductive material 37. On the other hand, the Nifilms 26 b-1 and 28 b-1 of the second metal films 26 b and 28 b havepoor bonding ability with the conductive material 37. The Pd films 26a-2, 28 a-2, 26 b-2, and 28 b-2 adjust the conductivity in the metalfilms as a whole, and maintain the film strength. The Pd films also havegood bonding ability with the wires.

When mounting the semiconductor device 21 onto the printed wiring board35, the contact surface must have excellent bonding ability with theconductive material 37 to obtain reliable mounting. This is the reasonthat the Au films 26 a-1 and 28 a-1 are employed.

Meanwhile, a portion indicated by A in FIG. 6 is exposed, and thisportion might be brought into contact with the conductive material 37when mounting is carried out. If the portion A of the second metal films26 b and 28 b is made of a material having excellent bonding abilitywith the conductive material 37, the conductive material 37 adheres tothe portion A as indicated by a broken line in FIG. 6, and theneighboring metal films are short-circuited with each other. To preventthis, the Ni films 26 b-1 and 28 b-1 having poor bonding ability withthe conductive material 37 are employed.

The materials for the metal films mentioned above are mere examples.Other materials can be employed for the metal films, as long as thematerials have the functions mentioned above.

FIGS. 7a and 7B are a sectional view and a perspective view of asemiconductor device of a third embodiment of the present invention.

A semiconductor device 41 of the third embodiment has a semiconductorchip 42 included in a grounding protrusion 47 of a resin package 43, asshown in FIG. 7A. The resin package 43 is provided with mountingprotrusions 45 and the grounding protrusion 47. Metal films 46 and 48cover the surfaces of the mounting protrusions 45 and the groundingprotrusion 47.

Signal terminals on the surface of the semiconductor chip 42 and themetal films 46 on the mounting protrusions 45 are electrically connectedby wires 44.

The bottom surface of the semiconductor chip 42 sealed in the groundingprotrusions 47 of the resin package 43 is in electrical contact with themetal film 48 via a conductive adhesive 49.

As shown in FIG. 7B, the metal film 48 corresponding to the groundingprotrusion 47 is formed in the center of the semiconductor device 41,and the metal films 46 corresponding to the mounting protrusions 45 aresituated in the surrounding area of the metal film 48. One of the metalfilms 46 is connected to the metal film 48 by a connecting portion 50.

The connecting portion 50 directly connects the metal films 46 and 48without wire bonding, so that the metal film 48 of the groundingprotrusion 47 can be grounded via the metal film 46 in a case where themetal film 48 is not in electrical contact with the printed circuitboard when mounting the semiconductor device 41 onto the printed circuitboard.

The above structure can be achieved by changing the resist pattern,which determines the shapes of the concavities and the metal films.

FIGS. 8A and 8B are a sectional view and a perspective view of asemiconductor device of a fourth embodiment of the present invention.

A semiconductor device 51 of the fourth embodiment has a semiconductorchip 52 in the center of the resin package 53 provided with mountingprotrusions 55, as shown in FIG. 8A. Metal films 56 and 58 cover themounting protrusions 55 and the bottom surface of the semiconductor chipmounting surface, respectively.

Signal terminals on the surface of the semiconductor chip 52 areelectrically connected to the metal films 56 on the mounting protrusions55 by wires 54.

The bottom surface of the semiconductor chip 52 sealed in the resinpackage 53 is in electrical contact with the metal film 58 via aconductive adhesive 59.

As shown in FIG. 8B, the semiconductor chip 52 is situated on the metalfilm 58 having an outer periphery portion. The metal films 56corresponding to the mounting protrusions 55 are situated in thesurrounding area of the metal film 58. One of the metal films 56 (agrounding terminal) is electrically connected to the metal film 58 by awire.

Since the metal film 58 for grounding is not in contact with the printedcircuit board in the semiconductor device 51 of this embodiment, themetal film 58, which absorbs noise of the semiconductor chip 52, isconnected to one of the metal films 56 by the wire. Thus, the noise isreleased through the metal film 56.

FIGS. 9A and 9B are a sectional view and a perspective view of asemiconductor device of a fifth embodiment of the present invention.

The fifth embodiment is a modification of the fourth embodiment. Asemiconductor device 61 of this embodiment has a semiconductor chip 62in the center of a resin package 63 provided with mounting protrusions65, as shown in FIG. 9A. Metal films 66 and 68 cover the mountingprotrusions 65 and the bottom surface of the semiconductor chip mountingsurface, respectively.

Signal terminals on the surface of the semiconductor chip 62 and themetal films 66 on the mounting protrusions 65 are electrically connectedby wires 64.

The bottom surface of the semiconductor chip 62 sealed in the resinpackage 63 is in electrical contact with the metal film 68 via aconductive adhesive 69.

As shown in FIG. 9B, the semiconductor chip 62 is situated on the metalfilm 68 having an outer periphery portion. The metal films 66corresponding to the mounting protrusions 65 are situated in thesurrounding area of the metal film 68. One of the metal films 66 iselectrically connected to the metal film 68 by a connecting portion 70.

The connecting portion 70 serves as the wire in the fourth embodiment,and can be formed by changing the resist pattern in the productionprocess.

FIGS. 10A and 10B are a sectional view and a perspective view of asemiconductor device of a sixth embodiment of the present invention.

A semiconductor device 71 of the sixth embodiment has a semiconductorchip 72 in the center of a resin package 73 having mounting protrusions75, as shown in FIG. 10A. The mounting protrusions 75 are covered withmetal films 76, and a metal plate 78 is buried in a lower portion of thesemiconductor device 72.

Signal terminals on the surface of the semiconductor device 72 and themetal films 76 on the mounting protrusions 75 are electrically connectedby wires 74.

The bottom surface of the semiconductor chip 72 sealed in the resinpackage 73 is in electrical contact with the metal plate 78 via aconductive adhesive 79.

As shown in FIG. 10B, the semiconductor chip 72 is situated on the metalplate 78 with an outer periphery portion, and the metal films 76corresponding to the mounting protrusions 75 are situated in thesurrounding area of the metal plate 78. One of the metal films 78 (agrounding terminal) is electrically connected to the metal plate 78 by awire.

In this embodiment, the grounding metal plate 78 below the semiconductorchip 72 is not exposed from the surface of the semiconductor device 71,but is buried in the resin package 73. Thus, the semiconductor chip 72is not adversely influenced by external noise.

Although the present invention has been fully described by way ofexamples with reference to the accompanying drawings, it is to be notedthat various changes and modifications will be apparent to those skilledin the art. Therefore, unless otherwise such changes and modificationsdepart from the scope of the present invention, they should be construedas being included therein.

The present application is based on Japanese priority application No.10-183988, filed on Jun. 30, 1998, the entire contents of which arehereby incorporated by reference.

What is claimed is:
 1. A semiconductor device comprising: asemiconductor chip; a resin package which seals the semiconductor chip;signal passages which guide signal terminals of the semiconductor chipoutward from the resin package; signal terminals formed on firstprotrusions of the resin package and connected to the signal passages; agrounding metal film on a second protrusion of the semiconductor chip,said second protrusion having an area wider than that of thesemiconductor chip; and a grounding passage connected to the groundingmetal film and guided outward from the resin package.
 2. Thesemiconductor device according to claim 1, wherein a surface of thegrounding metal film opposite to a surface thereof in contact with thebottom surface of the semiconductor chip is exposed from the resinpackage, thereby forming the grounding passage.
 3. The semiconductordevice according to claim 1, wherein the grounding metal film isconnected to a terminal exposed outside the resin package by aconductive wire or a conductive film, thereby forming the groundingpassage.
 4. The semiconductor device according to claim 1, wherein: theresin package has a plurality of said first protrusions covered withmetal films on a mounting surface thereof; and the metal films coveringthe first protrusions are connected to the signal terminals of thesemiconductor chip by conductive wires, thereby forming the signalpassages.
 5. The semiconductor device according to claim 4, wherein themetal films are disposed on inner surfaces of the concavities and onflat regions in neighborhood areas of the concavities.
 6. Thesemiconductor device according to claim 4, wherein: the resin package isprovided with a grounding protrusion in an area surrounded by the firstprotrusions on the mounting surface; and the grounding metal film incontact with the bottom surface of the semiconductor chip is exposedoutside the resin package through the grounding protrusion.
 7. Thesemiconductor device according to claim 5, wherein the resin package isprovided with a grounding protrusion in an area surrounded by the firstprotrusions on the mounting surface; and the grounding metal film incontact with the bottom surface of the semiconductor chip is exposedoutside the resin package through the grounding protrusion.
 8. Thesemiconductor device according to claim 1, wherein the first and secondprotrusions are located on a bottom side of the resin package.